US tenders for safer penetrator materials blaming opposition to depleted uranium
In a further sign that persistent international pressure over the use of DU weapons is having an impact, the US military is finally getting serious about the need to replace DU in its tank ammunition. A Department of Defense tender that closed in October, sought companies able to: “Identify and produce a low-cost material that matches or exceeds the performance of depleted uranium (DU) in kinetic energy (KE) penetrator applications.”
The tender Novel Materials for Kinetic Energy Penetrators cited ongoing opposition to DU as a key driver for the decision, admitting that: "Limited opposition to the use of DU exists in some circles based on the idea that, as a heavy metal, depleted uranium deposited on the battlefield might represent a serious persistent health or environmental hazard. Because of this opposition, the Army has been exploring alternative materials for KE penetrator applications."
ICBUW has previously reported on signs of a move away from DU in the US’s medium calibre ammunition and this year’s U-turn by the US over its threat to use DU in current operations in Iraq and Syria was testament to the increasing stigmatisation of the weapons. The widespread opposition to the use of DU is perhaps most apparent in the increasingly well supported UN General Assembly resolutions on the issue. Veterans groups in the US, and communities affected by firing ranges and production sites, have also been vocal in their opposition to the weapons.
“This is a clear sign that public opposition to the weapons is changing both the procurement and operational policy of their greatest advocate – the US,” said ICBUW Coordinator Doug Weir. “However, while welcome this is no reason for complacency, developing these alternatives will take time, other states continue to maintain DU stockpiles and there is still no clear obligation on users to address historical contamination in countries like Iraq, or to assist affected communities.”
Confluence of technology and public opposition
The US has been examining alternatives to DU in kinetic energy penetrators since shortly after their first major use in the 1991 Gulf War. Even in the early 90s, and in the wake of their widespread use in the conflict, it was clear that they would never prove to be acceptable to military personnel, allied states or the general public. In many respects this was unsurprising, as the casual dispersal of radioactive material in conflict runs counter to the most fundamental norms of radiation protection and clearly placed civilians and the environment at risk, in many cases for years after the end of hostilities.
As a result of this opposition, the US has been quietly funding laboratory research on alternative materials for many years. The challenge has been to identify materials of similar density, that are less toxic and that have similar physical characteristics to DU. The key characteristic has been something called adiabatic shear banding, this stops the point of the dart or penetrator becoming blunt as its passes through its target.
In the last few years, an increasing number of studies have demonstrated that grinding up tungsten and other metals into extremely fine powders and mixing them can create materials that have this key deformation property. Other lessons have also been learned. Along the way an increasing acceptance that whatever replaced DU would also need to be less toxic has also come to the fore. This led to the rejection of mixtures of tungsten, nickel and cobalt after it was found that rats developed extremely aggressive tumours when pellets of the alloy were implanted into them. These were thought to be caused by nickel and cobalt acting together to trigger tumour growth.
The tender that closed this October seems to suggest that the US Army is now confident enough about the development of these new materials that it feels that one can be chosen for testing and production. The process has also been aided by advances in the use of computers for modelling the characteristics of new materials.
The end of the beginning
While this decision is a positive step forward and recognition of the long-standing international opposition to the weapons, DU weapons will continue to be part of the US’s arsenal for many years to come. The latest update of their 120mm DU tank round for the Abrams tank has only just entered service and is expected to be in use for at least five years. Elsewhere, there is little evidence to suggest that either Russia or China are modifying their large calibre ammunition, nor is Pakistan.
France has been on the lookout for more “environmentally acceptable” materials for their tank ammunition for a number of years but it is unclear how advanced or committed they are. Meanwhile the UK still retains one 120mm tank round in spite of longstanding domestic opposition but its future appears to be bound tightly to that of the Challenger II tank, for which it was designed. A recent defence review called for the extension of the Challenger II’s lifespan, and presumably that of the its ammunition but the MoD has come under increasing pressure from the Scottish government over the testing of DU in south west Scotland.
Lack of clearance obligations
Although these signs of a move away from DU by the US and perhaps other P5 members are important, they do nothing to resolve the problems with existing contamination. While Serbia has dealt with the limited number of sites on its territory effectively, the same cannot be said for Bosnia or Kosovo. Iraq, the country most affected by the wartime use of DU is still struggling to deal with the legacy of contamination from 1991 and 2003.
Iraq has called for assistance from the international community in dealing with DU contamination, something made necessary by the singular lack of obligations on the users of the weapons to assist those affected. Contamination is costly and technically challenging to deal with and states should give serious thought to how such obligations could be developed.